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Carbon Monoxide Poisoning

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What's the Problem?

Carbon monoxide is often called a "silent killer." It is an odorless, colorless gas that can cause sudden illness and death. Carbon monoxide is found in combustion fumes, such as those produced by cars and trucks, small gasoline engines, houseboat and household generators, pressure washers, stoves, lanterns, burning charcoal and wood, and poorly functioning gas ranges and heating systems. Carbon monoxide from these sources can build up in enclosed or semi-enclosed spaces and poison people and animals in these spaces who breathe it. The most common symptoms of carbon monoxide poisoning are headache, dizziness, weakness, nausea, vomiting, chest pain, and confusion. High levels of carbon monoxide inhalation can cause loss of consciousness and death. Unless suspected, carbon monoxide poisoning can be difficult to diagnose because its symptoms mimic symptoms of other illnesses. People who are sleeping or intoxicated can die from carbon monoxide poisoning before ever experiencing symptoms.

Who's at Risk?

All people and animals are at risk for carbon monoxide poisoning; however, certain groups—fetuses; infants; and people with chronic heart disease, anemia, or respiratory problems—are more susceptible. Each year, nearly 500 unintentional deaths and more than 2,000 suicides are related to carbon monoxide poisoning in the United States.

Can It Be Prevented?

In Addition

Never use a gas range or oven to heat a home.

Never burn anything in a stove or fireplace that isn't vented.

Never use a charcoal grill, hibachi, lantern, or portable camping stove inside a home, tent, or camper.

Never run a motor vehicle, generator, or any gasoline-powered engine inside a basement, garage, or other enclosed structure (even if the doors or windows are open) or outside near an open door or window.

Yes, people can prevent carbon monoxide poisoning:

Have all fuel-burning appliances, such as furnaces, water heaters, and gas dryers, properly installed, maintained, and operated, and inspected annually by a qualified technician.

Periodically check and clean fireplace chimneys and flues.

Use unvented fuel-burning space heaters only while someone is awake to monitor them, and only while doors or windows in the room are open to provide ventilation.

Routinely inspect automobile exhaust systems, including catalytic converters, for defects, and routinely inspect tailpipes for blockage by snow, mud, or other substances.

Take part in swimming and other recreational activities only in areas away from where gasoline-powered engines, such as those on houseboats, vent their exhaust.

Never use portable electric generators in enclosed areas or in areas where the exhaust may vent through a door or window into a home or other building.

Install battery-operated carbon monoxide detectors in homes--in hallways near sleeping areas--as well as in houseboats and workplaces.

Change or check carbon monoxide detector batteries at the same time smoke detector batteries are checked or changed.

The Bottom Line

Carbon monoxide is a normal product of combustion that can be produced by any fuel-burning device. Carbon monoxide cannot be seen or smelled and it can rapidly cause illness and death, often before the victim is aware that anything is wrong. Proper maintenance and operation of fuel-burning devices and of carbon monoxide detectors can prevent carbon monoxide poisoning.

Case Examples

José and Maria, who recently emigrated from a warm Central American climate, lose electricity to their house during an ice storm. To heat their home and cook dinner, they start a small charcoal grill on top of their stove (to be safe from fire). They let the charcoal burn down and shut all the doors and windows tightly to keep in the heat when they go to bed. During the night, the electricity comes back on, turning on lights and waking up Maria. She tries to wake up Jose, but cannot. She calls 911 and he is taken to an emergency room and revived. The cause of his brush with death is carbon monoxide poisoning.

As a result of a hurricane, Dave, Anne, and their daughter Caitlin lose electrical power to their house. To keep their refrigerator running, Dave and Anne get out their portable generator. For many reasons: a) the weight of the generator, b) fear it will be stolen, c) wet and sometimes rainy weather, d) the short length of their extension cord and, e) lack of full appreciation of the carbon monoxide poisoning risks associated with a generator. Dave and Anne set it up in the doorway of their attached garage. They leave the door between the house and the garage cracked open for the cord to pass through. They fill up the generator's gas tank, start it, and go to bed. During the night Dave wakes up when the generator runs out of fuel and stops making noise. He is very dizzy and nauseous. When he tries to wake Anne and Caitlin he cannot. He calls 911 and they are all taken to the hospital emergency department, where Anne and Caitlin are revived. The cause of their symptoms is carbon monoxide poisoning.